U.S. patent application number 11/190190 was filed with the patent office on 2006-02-02 for body composition meter.
This patent application is currently assigned to TANITA CORPORATION. Invention is credited to Yasuhiro Kasahara.
Application Number | 20060025701 11/190190 |
Document ID | / |
Family ID | 35044612 |
Filed Date | 2006-02-02 |
United States Patent
Application |
20060025701 |
Kind Code |
A1 |
Kasahara; Yasuhiro |
February 2, 2006 |
Body composition meter
Abstract
There is provided a body composition meter capable of measuring
impedances in a specific body part easily and estimating body
composition indicators with high accuracy. The body composition
meter has a pair of current electrodes 3a and 3b disposed between a
pair of current electrodes 2a and 2b on adjustable arms 8a and 8b,
has a pair of measuring electrodes 4a and 4b disposed between the
innermost pair of current electrodes 3a and 3b, generates a current
between the current electrodes 2a and 2b or the current electrodes
3a and 3b in a current generating section, detects a voltage
generated between the measuring electrodes 4a and 4b in a voltage
detecting section when the current generating section generates a
current, and estimates body composition indicators based on all of
these detected voltages in body composition estimating means.
Inventors: |
Kasahara; Yasuhiro; (Tokyo,
JP) |
Correspondence
Address: |
MCDERMOTT WILL & EMERY LLP
600 13TH STREET, N.W.
WASHINGTON
DC
20005-3096
US
|
Assignee: |
TANITA CORPORATION
|
Family ID: |
35044612 |
Appl. No.: |
11/190190 |
Filed: |
July 27, 2005 |
Current U.S.
Class: |
600/547 |
Current CPC
Class: |
A61B 5/4872 20130101;
A61B 5/107 20130101; A61B 5/4869 20130101; A61B 5/0537 20130101;
A61B 5/6823 20130101; A61B 5/6835 20130101 |
Class at
Publication: |
600/547 |
International
Class: |
A61B 5/05 20060101
A61B005/05 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 27, 2004 |
JP |
2004-218697 |
Jun 6, 2005 |
JP |
2005-166241 |
Claims
1. A body composition meter comprising: multiple pairs of current
electrodes, a pair of measuring electrodes, a current generating
section, voltage detecting section, and body composition estimating
means, wherein the multiple pairs of current electrodes are
disposed on a specific body part sequentially at smaller spacings,
the measuring electrodes are disposed between the innermost pair of
current electrodes, the current generating section generates a
current between each pair of current electrodes, the voltage
detecting section detects a voltage generated between the measuring
electrodes when the current generating section generates a current
between each pair of current electrodes, and the body composition
estimating means estimates body composition indicators based on all
of the voltages detected by the voltage detecting section.
2. The body composition meter according to claim 1, further
comprising: a body part width acquiring section, and a display
section, wherein the body part width acquiring section acquires the
width of the specific body part, and the display section displays
the specific body part width acquired by the body part width
acquiring section as the width of the shape of a displayed cross
section of the specific body part and displays the body composition
indicators estimated by the body composition estimating means as
the size of the inside of the displayed cross section of the
specific body part at the magnification used to display the width
of the specific body part.
3. The body composition meter according to claim 1, further
comprising a support that supports the multiple pairs of current
electrodes and the measuring electrodes to make the electrodes
contact the specific body part.
4. The body composition meter according to claim 3, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
5. The body composition meter according to claim 4, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
6. The body composition meter according to claim 5, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
7. The body composition meter according to claim 3, wherein the
support has a shape which fits the shape of the surface of the
specific body part that makes contact with the electrodes and has a
flexible portion at least in a portion thereof.
8. The body composition meter according to claim 7, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
9. The body composition meter according to claim 8, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
10. The body composition meter according to claim 9, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
11. The body composition meter according to claim 1, wherein the
current generating section generates a current such that the
frequency of the current gradually lowers from the outermost pair
of current electrodes to the innermost pair of current
electrodes.
12. The body composition meter according to claim 11, further
comprising: a body part width acquiring section, and a display
section, wherein the body part width acquiring section acquires the
width of the specific body part, and the display section displays
the specific body part width acquired by the body part width
acquiring section as the width of the shape of a displayed cross
section of the specific body part and displays the body composition
indicators estimated by the body composition estimating means as
the size of the inside of the displayed cross section of the
specific body part at the magnification used to display the width
of the specific body part.
13. The body composition meter according to claim 11, further
comprising a support that supports the multiple pairs of current
electrodes and the measuring electrodes to make the electrodes
contact the specific body part.
14. The body composition meter according to claim 13, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
15. The body composition meter according to claim 14, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
16. The body composition meter according to claim 15, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
17. The body composition meter according to claim 13, wherein the
support has a shape which fits the shape of the surface of the
specific body part that makes contact with the electrodes and has a
flexible portion at least in a portion thereof.
18. The body composition meter according to claim 17, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
19. The body composition meter according to claim 18, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
20. The body composition meter according to claim 19, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
21. The body composition meter according to claim 11, wherein the
current generating section generates a current of specific
frequency ranging from 128 kHz to 512 kHz between the outermost
pair of current electrodes and generates a current of specific
frequency ranging from 4 kHz to 12.5 kHz between the innermost pair
of current electrodes.
22. The body composition meter according to claim 21, further
comprising: a body part width acquiring section, and a display
section, wherein the body part width acquiring section acquires the
width of the specific body part, and the display section displays
the specific body part width acquired by the body part width
acquiring section as the width of the shape of a displayed cross
section of the specific body part and displays the body composition
indicators estimated by the body composition estimating means as
the size of the inside of the displayed cross section of the
specific body part at the magnification used to display the width
of the specific body part.
23. The body composition meter according to claim 21, further
comprising a support that supports the multiple pairs of current
electrodes and the measuring electrodes to make the electrodes
contact the specific body part.
24. The body composition meter according to claim 23, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
25. The body composition meter according to claim 24, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
26. The body composition meter according to claim 25, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
27. The body composition meter according to claim 23, wherein the
support has a shape which fits the shape of the surface of the
specific body part that makes contact with the electrodes and has a
flexible portion at least in a portion thereof.
28. The body composition meter according to claim 27, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
29. The body composition meter according to claim 28, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
30. The body composition meter according to claim 29, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
31. The body composition meter according to claim 21, wherein the
specific frequency ranging from 128 kHz to 512 kHz is a frequency
of 256 kHz, and the specific frequency ranging from 4 kHz to 12.5
kHz is a frequency of 5 kHz.
32. The body composition meter according to claim 31, further
comprising: a body part width acquiring section, and a display
section, wherein the body part width acquiring section acquires the
width of the specific body part, and the display section displays
the specific body part width acquired by the body part width
acquiring section as the width of the shape of a displayed cross
section of the specific body part and displays the body composition
indicators estimated by the body composition estimating means as
the size of the inside of the displayed cross section of the
specific body part at the magnification used to display the width
of the specific body part.
33. The body composition meter according to claim 31, further
comprising a support that supports the multiple pairs of current
electrodes and the measuring electrodes to make the electrodes
contact the specific body part.
34. The body composition meter according to claim 33, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
35. The body composition meter according to claim 34, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
36. The body composition meter according to claim 35, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
37. The body composition meter according to claim 33, wherein the
support has a shape which fits the shape of the surface of the
specific body part that makes contact with the electrodes and has a
flexible portion at least in a portion thereof.
38. The body composition meter according to claim 37, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
39. The body composition meter according to claim 38, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
40. The body composition meter according to claim 39, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
41. The body composition meter according to claim 1, wherein the
body composition estimating means comprises: an impedance computing
section, a body composition computing equation storage section, and
a body composition computing section, wherein the impedance
computing section computes an impedance based on a current
generated between each pair of current electrodes by the current
generating section and a voltage detected by the voltage detecting
section, the body composition computing equation storage section
stores body composition computing equations for computing body
composition indicators based on all of the impedances computed by
the impedance computing section, and the body composition computing
section computes body composition indicators by substituting the
impedances computed by the impedance computing section into the
body composition computing equations stored in the body composition
computing equation storage section.
42. The body composition meter according to claim 41, further
comprising: a body part width acquiring section, and a display
section, wherein the body part width acquiring section acquires the
width of the specific body part, and the display section displays
the specific body part width acquired by the body part width
acquiring section as the width of the shape of a displayed cross
section of the specific body part and displays the body composition
indicators estimated by the body composition estimating means as
the size of the inside of the displayed cross section of the
specific body part at the magnification used to display the width
of the specific body part.
43. The body composition meter according to claim 41, further
comprising a support that supports the multiple pairs of current
electrodes and the measuring electrodes to make the electrodes
contact the specific body part.
44. The body composition meter according to claim 43, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
45. The body composition meter according to claim 44, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
46. The body composition meter according to claim 45, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
47. The body composition meter according to claim 43, wherein the
support has a shape which fits the shape of the surface of the
specific body part that makes contact with the electrodes and has a
flexible portion at least in a portion thereof.
48. The body composition meter according to claim 47, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
49. The body composition meter according to claim 48, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
50. The body composition meter according to claim 49, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
51. The body composition meter according to claim 41, wherein the
current generating section generates a current such that the
frequency of the current gradually lowers from the outermost pair
of current electrodes to the innermost pair of current
electrodes.
52. The body composition meter according to claim 51, further
comprising: a body part width acquiring section, and a display
section, wherein the body part width acquiring section acquires the
width of the specific body part, and the display section displays
the specific body part width acquired by the body part width
acquiring section as the width of the shape of a displayed cross
section of the specific body part and displays the body composition
indicators estimated by the body composition estimating means as
the size of the inside of the displayed cross section of the
specific body part at the magnification used to display the width
of the specific body part.
53. The body composition meter according to claim 51, further
comprising a support that supports the multiple pairs of current
electrodes and the measuring electrodes to make the electrodes
contact the specific body part.
54. The body composition meter according to claim 53, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
55. The body composition meter according to claim 54, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
56. The body composition meter according to claim 55, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
57. The body composition meter according to claim 53, wherein the
support has a shape which fits the shape of the surface of the
specific body part that makes contact with the electrodes and has a
flexible portion at least in a portion thereof.
58. The body composition meter according to claim 57, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
59. The body composition meter according to claim 58, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
60. The body composition meter according to claim 59, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
61. The body composition meter according to claim 51, wherein the
current generating section generates a current of specific
frequency ranging from 128 kHz to 512 kHz between the outermost
pair of current electrodes and generates a current of specific
frequency ranging from 4 kHz to 12.5 kHz between the innermost pair
of current electrodes.
62. The body composition meter according to claim 61, further
comprising: a body part width acquiring section, and a display
section, wherein the body part width acquiring section acquires the
width of the specific body part, and the display section displays
the specific body part width acquired by the body part width
acquiring section as the width of the shape of a displayed cross
section of the specific body part and displays the body composition
indicators estimated by the body composition estimating means as
the size of the inside of the displayed cross section of the
specific body part at the magnification used to display the width
of the specific body part.
63. The body composition meter according to claim 61, further
comprising a support that supports the multiple pairs of current
electrodes and the measuring electrodes to make the electrodes
contact the specific body part.
64. The body composition meter according to claim 63, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
65. The body composition meter according to claim 64, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
66. The body composition meter according to claim 65, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
67. The body composition meter according to claim 63, wherein the
support has a shape which fits the shape of the surface of the
specific body part that makes contact with the electrodes and has a
flexible portion at least in a portion thereof.
68. The body composition meter according to claim 67, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
69. The body composition meter according to claim 68, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
70. The body composition meter according to claim 69, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
71. The body composition meter according to claim 61, wherein the
specific frequency ranging from 128 kHz to 512 kHz is a frequency
of 256 kHz, and the specific frequency ranging from 4 kHz to 12.5
kHz is a frequency of 5 kHz.
72. The body composition meter according to claim 71, further
comprising: a body part width acquiring section, and a display
section, wherein the body part width acquiring section acquires the
width of the specific body part, and the display section displays
the specific body part width acquired by the body part width
acquiring section as the width of the shape of a displayed cross
section of the specific body part and displays the body composition
indicators estimated by the body composition estimating means as
the size of the inside of the displayed cross section of the
specific body part at the magnification used to display the width
of the specific body part.
73. The body composition meter according to claim 71, further
comprising a support that supports the multiple pairs of current
electrodes and the measuring electrodes to make the electrodes
contact the specific body part.
74. The body composition meter according to claim 73, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
75. The body composition meter according to claim 74, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
76. The body composition meter according to claim 75, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
77. The body composition meter according to claim 73, wherein the
support has a shape which fits the shape of the surface of the
specific body part that makes contact with the electrodes and has a
flexible portion at least in a portion thereof.
78. The body composition meter according to claim 77, wherein the
support comprises: a body part width acquiring section, and a
display section, wherein the body part width acquiring section
measures the width of the specific body part, and the display
section displays the specific body part width measured by the body
part width acquiring section as the width of the shape of a
displayed cross section of the specific body part and displays the
body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
79. The body composition meter according to claim 78, wherein the
body part width acquiring section comprises: an adjustable arm, and
encoders, wherein the adjustable arm expands or contracts in the
width direction of the specific body part to fit around the
specific body part, and the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
80. The body composition meter according to claim 79, wherein the
body part width acquiring section further comprises: contact
detecting sensors, and a driving motor, wherein the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part, and the driving motor expands or contracts
the adjustable arm and stops the adjustable arm at positions where
the contact detecting sensors detect that the adjustable arm is
fitted around the specific body part.
81. The body composition meter according to claim 80, wherein the
specific body part is the abdomen of a body, and the body
composition indicator is at least one selected from the group
consisting of a subcutaneous fat thickness, an abdominal muscle
thickness, a subcutaneous fat area, a visceral fat area, a total
abdominal fat area, a truncal fat percentage and a whole body fat
percentage.
82. The body composition meter according to claim 81, wherein the
distance between the multiple pairs of current electrodes and the
measuring electrodes is a specific distance ranging from 4 cm to 10
cm.
83. The body composition meter according to claim 82, wherein the
distance between the measuring electrodes is 8 cm.
84. The body composition meter according to claim 82, wherein the
specific distance between the outermost pair of current electrodes
and the measuring electrodes is 8 cm, and the specific distance
between the innermost pair of current electrodes and the measuring
electrodes is 4 cm to 5 cm.
85. The body composition meter according to claim 84, wherein the
distance between the measuring electrodes is 8 cm.
86. The body composition meter according to any one of claims 3,
13, 23, 33, 43, 53, 63 or 73, wherein the support changes the
distances between ones of the current electrodes and the others of
the current electrodes and the distance between one of the
measuring electrodes and the other of the measuring electrodes
according to the width of the specific body part.
87. The body composition meter according to claim 1, further
comprising a body part width acquiring section which acquires the
width of the specific body part, the body composition estimating
means comprising: an impedance computing section, a body
composition computing equation storage section, and a body
composition computing section, wherein the impedance computing
section computes an impedance based on a current generated between
each pair of current electrodes by the current generating section
and a voltage detected by the voltage detecting section, the body
composition computing equation storage section stores body
composition computing equations for computing body composition
indicators based on the width of the specific body part acquired by
the body part width acquiring section and all of the impedances
computed by the impedance computing section, and the body
composition computing section computes body composition indicators
by substituting the impedances computed by the impedance computing
section into the body composition computing equations stored in the
body composition computing equation storage section.
88. The body composition meter according to claim 87, wherein the
current generating section generates a current such that the
frequency of the current gradually lowers from the outermost pair
of current electrodes to the innermost pair of current
electrodes.
89. The body composition meter according to claim 88, wherein the
current generating section generates a current of specific
frequency ranging from 128 kHz to 512 kHz between the outermost
pair of current electrodes and generates a current of specific
frequency ranging from 4 kHz to 12.5 kHz between the innermost pair
of current electrodes.
90. The body composition meter according to claim 20, wherein the
specific frequency ranging from 128 kHz to 512 kHz is a frequency
of 256 kHz, and the specific frequency ranging from 4 kHz to 12.5
kHz is a frequency of 5 kHz.
Description
BACKGROUND OF THE INVENTION
[0001] (i) Field of the Invention
[0002] This invention relates to a body composition meter capable
of measuring impedances in a specific body part and estimating body
composition indicators.
[0003] (ii) Description of the Related Art
[0004] In this field, body fat meters capable of measuring an
impedance which occurs between both feet, both hands or a hand and
a foot and estimating the body fat percentage of a whole body which
is a body composition indicator are introduced to the market from
the viewpoint of a health-oriented life, and along with an increase
in desire for the health-oriented life, further research and
development have been made, and body fat meters capable of
measuring an impedance in the abdomen and estimating a subcutaneous
fat amount and a visceral fat amount in the abdomen which are body
composition indicators are disclosed.
[0005] Body fat meters disclosed in patent publications, i.e.,
those capable of estimating a subcutaneous fat amount and a
visceral fat amount in the abdomen, attach current electrodes and
measuring electrodes on a subject, pass a current between the
current electrodes, and measure a voltage generated in the abdomen
between the measuring electrodes when the current is passed between
the current electrodes. All of these body fat meters are easy to
use and capable of highly accurate measurements and
estimations.
Patent Publication 1
[0006] Japanese Patent Laid-Open Publication No. 2001-178697
Patent Publication 2
[0007] Japanese Patent Laid-Open Publication No. 2001-252256
Patent Publication 3
[0008] Japanese Patent Laid-Open Publication No. 2001-252257
Patent Publication 4
[0009] Japanese Patent Laid-Open Publication No. 2002-238871
Patent Publication 5
[0010] Japanese Patent Laid-Open Publication No. 2002-369806
Patent Publication 6
[0011] Japanese Patent Laid-Open Publication No. 2004-135698
Patent Publication 7
[0012] Japanese Patent Laid-Open Publication No. 2004-141186
[0013] However, despite the above background, body fat meters which
are easier to use and capable of more accurate measurements and
estimations are demanded in the market.
[0014] Technical key points in improving the ease of use and
accuracy of the body fat meters which measure an impedance in the
abdomen and estimate a subcutaneous fat amount and a visceral fat
amount in the abdomen are relative locations of the current
electrodes and the measuring electrodes and a detection method
therefor.
[0015] Thus, under the above circumstances, an object of the
present invention is to provide a body composition meter which
differs from the body fat meters disclosed in the patent
publications in relative locations of current electrodes and
measuring electrodes and detection method therefor and is capable
of measuring impedances in a specific body part easily and
estimating body composition indicators with high accuracy.
SUMMARY OF THE INVENTION
[0016] A body composition meter of the present invention comprises:
[0017] multiple pairs of current electrodes, [0018] a pair of
measuring electrodes, [0019] a current generating section, [0020] a
voltage detecting section, and [0021] body composition estimating
means, [0022] wherein [0023] the multiple pairs of current
electrodes are disposed on a specific body part sequentially at
smaller spacings, [0024] the measuring electrodes are disposed
between the innermost pair of current electrodes, [0025] the
current generating section generates a current between each pair of
current electrodes, [0026] the voltage detecting section detects a
voltage generated between the measuring electrodes when the current
generating section generates a current between each pair of current
electrodes, and [0027] the body composition estimating means
estimates body composition indicators based on all of the voltages
detected by the voltage detecting section.
[0028] Further, the body composition estimating means comprises:
[0029] an impedance computing section, [0030] a body composition
computing equation storage section, and [0031] a body composition
computing section, [0032] wherein [0033] the impedance computing
section computes an impedance based on a current generated between
each pair of current electrodes by the current generating section
and a voltage detected by the voltage detecting section, [0034] the
body composition computing equation storage section stores body
composition computing equations for computing body composition
indicators based on all of the impedances computed by the impedance
computing section, and [0035] the body composition computing
section computes body composition indicators by substituting the
impedances computed by the impedance computing section into the
body composition computing equations stored in the body composition
computing equation storage section.
[0036] Further, the body composition meter further comprises:
[0037] a body part width acquiring section, and [0038] a display
section, [0039] wherein [0040] the body part width acquiring
section acquires the width of the specific body part, and [0041]
the display section displays the specific body part width acquired
by the body part width acquiring section as the width of the shape
of a displayed cross section of the specific body part and displays
the body composition indicators estimated by the body composition
estimating means as the size of the inside of the displayed cross
section of the specific body part at the magnification used to
display the width of the specific body part.
[0042] Further, the body composition meter further comprises a
support that supports the multiple pairs of current electrodes and
the measuring electrodes to make the electrodes contact the
specific body part.
[0043] Further, the support has a shape which fits the shape of the
surface of the specific body part that makes contact with the
electrodes and has a flexible portion at least in a portion
thereof.
[0044] Further, the support comprises: [0045] a body part width
acquiring section, and [0046] a display section, [0047] wherein
[0048] the body part width acquiring section measures the width of
the specific body part, and [0049] the display section displays the
specific body part width measured by the body part width acquiring
section as the width of the shape of a displayed cross section of
the specific body part and displays the body composition indicators
estimated by the body composition estimating means as the size of
the inside of the displayed cross section of the specific body part
at the magnification used to display the width of the specific body
part.
[0050] Further, the body part width acquiring section comprises:
[0051] an adjustable arm, and [0052] encoders, [0053] wherein
[0054] the adjustable arm expands or contracts in the width
direction of the specific body part to fit around the specific body
part, and [0055] the encoders detect the distance when the
adjustable arm is fitted around the specific body part.
[0056] Further, the body part width acquiring section further
comprises: [0057] contact detecting sensors, and [0058] a driving
motor, [0059] wherein [0060] the contact detecting sensors detect
that the adjustable arm is fitted around the specific body part,
and [0061] the driving motor expands or contracts the adjustable
arm and stops the adjustable arm at positions where the contact
detecting sensors detect that the adjustable arm is fitted around
the specific body part.
[0062] Further, the specific body part is the abdomen of a body,
and the body composition indicator is at least one selected from
the group consisting of a subcutaneous fat thickness, an abdominal
muscle thickness, a subcutaneous fat area, a visceral fat area, a
total abdominal fat area, a truncal fat percentage and a whole body
fat percentage.
[0063] Further, the distance between the multiple pairs of current
electrodes and the measuring electrodes is a specific distance
ranging from 4 cm to 10 cm.
[0064] Further, the specific distance between the outermost pair of
current electrodes and the measuring electrodes is 8 cm, and the
specific distance between the innermost pair of current electrodes
and the measuring electrodes is 4 cm to 5 cm.
[0065] Further, the distance between the measuring electrodes is 8
cm.
[0066] Further, the support changes the distances between ones of
the current electrodes and the others of the current electrodes and
the distance between one of the measuring electrodes and the other
of the measuring electrodes according to the width of the specific
body part.
[0067] Further, the body composition meter further comprises a body
part width acquiring section which acquires the width of the
specific body part, and [0068] the body composition estimating
means comprises: [0069] an impedance computing section, [0070] a
body composition computing equation storage section, and [0071] a
body composition computing section, [0072] wherein [0073] the
impedance computing section computes an impedance based on a
current generated between each pair of current electrodes by the
current generating section and a voltage detected by the voltage
detecting section, [0074] the body composition computing equation
storage section stores body composition computing equations for
computing body composition indicators based on the width of the
specific body part acquired by the body part width acquiring
section and all of the impedances computed by the impedance
computing section, and [0075] the body composition computing
section computes body composition indicators by substituting the
impedances computed by the impedance computing section into the
body composition computing equations stored in the body composition
computing equation storage section.
[0076] Further, the current generating section generates a current
such that the frequency of the current gradually lowers from the
outermost pair of current electrodes to the innermost pair of
current electrodes.
[0077] Further, the current generating section generates a current
of specific frequency ranging from 128 kHz to 512 kHz between the
outermost pair of current electrodes and generates a current of
specific frequency ranging from 4 kHz to 12.5 kHz between the
innermost pair of current electrodes.
[0078] Further, the specific frequency ranging from 128 kHz to 512
kHz is a frequency of 256 kHz, and the specific frequency ranging
from 4 kHz to 12.5 kHz is a frequency of 5 kHz.
[0079] The body composition meter of the present invention has the
multiple pairs of current electrodes placed on a specific body part
successively at smaller spacings, generates a current between each
pair of current electrodes in the current generating section,
detects a voltage generated between the measuring electrodes when
the current generating section generates a current between each
pair of current electrodes in the voltage detecting section, and
estimates body composition indicators based on all of these
detected voltages in the body composition estimating means. Thus,
by use of the above body composition meter, a user can estimate
highly accurate body composition indicators taking into
consideration the degree of current dependence on layers which are
relatively shallow, relatively medium and relatively deep from the
surface of a specific body part on which the electrodes are
disposed, as easily as the user places the electrodes on the
specific body part.
[0080] Further, the body composition estimating means estimates
body composition indicators merely by substituting impedances
computed by the impedance computing section into the body
composition computing equations stored in the body composition
computing equation storage section to compute the body composition
indicators in the body composition computing section. Thereby, a
user can estimate body composition indicators more easily.
[0081] Further, the display section displays the width of the shape
of a displayed cross section of the specific body part and the size
of body composition indicators of the inside of the displayed cross
section at the same magnification as the actual width of a cross
section of the specific body part and the actual size of body
composition indicators of the inside of the cross section. Thereby,
a user can know the accurate condition of a cross section of the
specific body part easily.
[0082] Further, the multiple pairs of current electrodes and the
measuring electrodes are disposed on the support. Thereby, the
electrodes can be contacted with the specific body part easily.
[0083] Further, the support has a shape which fits the shape of the
surface of the specific body part that contacts the electrodes and
has a flexible portion at least in a portion thereof. Thereby, the
support can be contacted with the specific body part
accurately.
[0084] Further, the support also serves as the body part width
acquiring section, and the display section displays the width of
the shape of a displayed cross section of the specific body part
and the size of body composition indicators of the inside of the
displayed cross section at the same magnification as the actual
width of a cross section of the specific body part and the actual
size of body composition indicators of the inside of the cross
section. Thereby, a user can know the accurate condition of a cross
section of the specific body part more easily.
[0085] Further, in the body part width acquiring section, the
adjustable arm is fitted around the specific body part, and the
encoders detect the distance when the adjustable arm is fitted
around the specific body part. Thereby, a user can acquire the
width of the body part easily even in a lying position.
[0086] Further, in the body part width acquiring section, the
driving motor extends or contracts the adjustable arm automatically
and stops the movement of the adjustable arm at a position where
the contact detecting sensors have detected that the adjustable arm
is fitted around the specific body part. Thus, a user can acquire
the width of the body part more easily.
[0087] Further, the specific body part is the abdomen of a body,
and the body composition indicator is at least one selected from
the group consisting of a subcutaneous fat thickness, an abdominal
muscle thickness, a subcutaneous fat area, a visceral fat area, a
total abdominal fat area, a truncal fat percentage and a whole body
fat percentage. Thus, a user can easily estimate at least one
selected from the group consisting of a subcutaneous fat thickness,
an abdominal muscle thickness, a subcutaneous fat area, a visceral
fat area, a total abdominal fat area, a truncal fat percentage and
a whole body fat percentage from the abdomen of a body.
[0088] Further, the distance between the multiple pairs of current
electrodes and the measuring electrodes is a specific distance
ranging from 4 cm to 10 cm. Thereby, a current can be passed from
the current generating section with good dependency on the layers
from the surface of the specific body part, and estimation accuracy
can be increased.
[0089] Further, the specific distance between the outermost pair of
current electrodes and the measuring electrodes is 8 cm, and the
specific distance between the innermost pair of current electrodes
and the measuring electrodes is 4 cm to 5 cm. Thereby, a current
can be passed from the current generating section with better
dependency on the layers from the surface of the specific body part
with higher dependency, and estimation accuracy can be further
increased.
[0090] Further, the distance between the measuring electrodes is 8
cm. Thus, a voltage corresponding to a current passing depending on
the layers from the surface of the specific body part can be
detected in the voltage detecting section with high accuracy, and
estimation accuracy can be further increased.
[0091] Further, the support changes the distances between ones of
the current electrodes and the others of the current electrodes and
the distance between one of the measuring electrodes and the other
of the measuring electrodes according to the width of the specific
body part. Thereby, regardless of the width of the specific body
part, accurate impedances in the abdomen can be obtained, and body
composition indicators can be estimated.
[0092] Further, the body composition estimating means estimates
body composition indicators merely by substituting the width of the
specific body part acquired by the body part width acquiring
section and impedances computed by the impedance computing section
into the body composition computing equations stored in the body
composition computing equation storage section to compute the body
composition indicators in the body composition computing section.
Thereby, a user can estimate body composition indicators more
accurately and more easily.
[0093] Further, the current generating section generates a current
such that the frequency of the current gradually lowers from the
outermost pair of current electrodes to the innermost pair of
current electrodes. Thereby, voltages can be detected according to
distribution of tissues in the specific body part in the voltage
detecting section, and estimation accuracy can be increased.
[0094] Further, the current generating section generates a current
of specific frequency ranging from 128 kHz to 512 kHz between the
outermost pair of current electrodes and a current of specific
frequency ranging from 4 kHz to 12.5 kHz between the innermost pair
of current electrodes. Thereby, voltages with a high degree of
reflection can be detected according to distribution of tissues in
the specific body part in the voltage detecting section, and
estimation accuracy can be further increased.
[0095] Further, the current generating section generates a current
of 256 kHz between the outermost pair of current electrodes and a
current of 5 kHz between the innermost pair of current electrodes.
Thereby, voltages with a higher degree of reflection can be
detected according to distribution of tissues in the specific body
part in the voltage detecting section, and estimation accuracy can
be further increased.
BRIEF DESCRIPTION OF THE DRAWINGS
[0096] FIG. 1 is diagrams illustrating an external structure of a
body composition meter according to the present invention, wherein
A is a plan view and B is a front view (Example 1).
[0097] FIG. 2 is a block diagram illustrating the constitution of
the body composition meter according to the present invention
(Examples 1 and 2).
[0098] FIG. 3 is a block diagram illustrating the operation
procedures of the body composition meter according to the present
invention (Examples 1 and 2).
[0099] FIG. 4 is a graph illustrating the correlation between a
subcutaneous fat thickness measured by CT scanning and a
subcutaneous fat thickness computed by a body composition computing
equation (Example 1).
[0100] FIG. 5 is a graph illustrating the correlation between an
abdominal muscle thickness measured by CT scanning and an abdominal
muscle thickness computed by a body composition computing equation
(Example 1).
[0101] FIG. 6 is a graph illustrating the correlation between a
subcutaneous fat area measured by CT scanning and a subcutaneous
fat area computed by a body composition computing equation (Example
1).
[0102] FIG. 7 is a graph illustrating the correlation between a
visceral fat area measured by CT scanning and a visceral fat area
computed by a body composition computing equation (Example 1).
[0103] FIG. 8 is a graph illustrating the correlation between a
total abdominal fat area measured by CT scanning and a total
abdominal fat area computed by a body composition computing
equation (Example 1).
[0104] FIG. 9 is a graph illustrating the correlation between a
truncal fat percentage measured by DXA and a truncal fat percentage
computed by a body composition computing equation (Example 1).
[0105] FIG. 10 is a graph illustrating the correlation between a
whole body fat percentage measured by DXA and a truncal fat
percentage measured by DXA (Example 1).
[0106] FIG. 11 is a graph illustrating the correlation between a
truncal fat percentage measured by DXA and the reciprocal of a
measured abdominal impedance (Example 1).
[0107] FIG. 12 is diagrams illustrating examples of screens
displayed in the display section, wherein A is a diagram
illustrating an initial screen, B and C are diagrams illustrating
screens displaying estimation results, and D is a diagram
illustrating a screen for inquiring for remeasurement (Examples 1
and 2).
[0108] FIG. 13 is diagrams illustrating the principle of why body
composition indicators can be determined, wherein A is a
cross-sectional view of an abdominal portion which contacts the
electrodes, B is a three dimensional view of the abdominal portion
which contacts the electrodes, and C is a three dimensional view of
an abdominal portion to be detected.
[0109] FIG. 14 is an electrical equivalent circuit model diagram of
the abdomen of a body.
[0110] FIG. 15 is diagrams illustrating another external structure
of the body composition meter according to the present invention,
wherein A is a plan view and B is a front view.
[0111] FIG. 16 is diagrams illustrating another external structure
of the body composition meter according to the present invention,
wherein A is a plan view and B is a front view.
[0112] FIG. 17 is diagrams illustrating an external structure of a
body composition meter according to the present invention, wherein
A is a plan view and B is a front view (Example 2).
[0113] FIG. 18 is diagrams illustrating another external structure
of the body composition meter according to the present invention,
wherein A is a plan view and B is a front view.
[0114] FIG. 19 is diagrams illustrating another external structure
of the body composition meter according to the present invention,
wherein A is a plan view and B is a front view.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0115] The body composition meter of the present invention at least
comprises multiple pairs of current electrodes, a pair of measuring
electrodes, a current generating section, a voltage detecting
section and body composition estimating means, measures impedances
in a specific body part, and estimates indicators (such as an
amount, thickness, area and percentage) associated with body
composition (which is generally used as generic term for body fat,
visceral fat, subcutaneous fat, muscles, bones, body water and
other body constituents).
[0116] The multiple pairs of current electrodes are disposed on a
specific body part successively at smaller spacings. The measuring
electrodes are disposed between the innermost pair of current
electrodes. The current generating section generates a current
between each pair of current electrodes out of the multiple pairs
of current electrodes. The current generating section generates a
current such that the frequency of the current gradually lowers
from the outermost pair of current electrodes to the innermost pair
of current electrodes. The voltage detecting section detects a
voltage generated between the measuring electrodes when the current
generating section generates a current between each pair of current
electrodes. The body composition estimating means estimates body
composition indicators based on all of the voltages detected by the
voltage detecting section.
[0117] Next, the principle of why body composition indicators can
be determined by measuring impedances in a specific body part will
be described by use of FIG. 13. FIG. 13 is model diagrams for
illustrating the principle when a pair of current electrodes and a
pair of measuring electrodes are disposed on the navel side of the
abdomen of a body. FIG. 13A is a cross-sectional view of the
abdomen, FIG. 13B is a three dimensional view of a portion sliced
out of the abdomen, and FIG. 13C is a three dimensional view of a
sliced abdominal portion between the measuring electrodes.
[0118] It can be conceived that generating a current between a pair
of current electrodes 101a and 101b to pass the current through an
abdomen 100 and detecting a voltage between a pair of measuring
electrodes 102a and 102b by the measuring electrodes 102a and 102b
is equivalent to detecting a voltage when a current is passed
through a conductor (object to be measured) which has a cross
section A formed by the thickness aW in the anteroposterior
direction (navel-back direction) of the abdomen 100 and the length
c of the electrodes and a length bW between the measuring
electrodes 102a and 102b. Further, it can be conceived that a body
composition represents electrical resistivity since it reflects
ease of passing of current.
[0119] Further, as is known, an impedance is represented by
Z=.rho.L/S (Z: impedance, .rho.: electrical resistivity, L: length,
S: cross section). Thus, electrical resistivity .rho. for the
specific area of the abdomen 100 of the body can be determined by
substituting the cross section A formed by the thickness aW in the
anteroposterior direction of the abdomen 100 and the length c of
the electrodes into S, substituting the length bW between the
measuring electrodes 102a and 102b into L, and substituting an
impedance V/I based on a current I generated between the current
electrodes 101a and 101b and a voltage V generated between the
measuring electrodes 102a and 102b into Z. That is, measuring an
impedance in a specific body part is equivalent to measuring an
indicator associated with a body composition reflecting ease of
passing of current in the specific body part.
[0120] The validity of such a principle is also validated by a fact
that the reciprocal of a measured abdominal impedance has a
correlation with a truncal fat percentage which is a body
composition indicator measured by DXA which is generally considered
to have high estimation accuracy, as shown in the graph of FIG. 11
illustrating the correlation, for example.
[0121] Although a body composition indicator can be determined by
such a principle, body composition distribution is not uniform from
the surface of a specific body part toward the center of a body,
and current density distribution from the surface of the specific
body part toward the center of the body varies according to the
distance between a pair of current electrodes disposed on the
surface of the specific body part, when the specific body part is a
cross section as shown in FIG. 13A. Thus, the accuracy of
measurement of impedance may be low when a pair of current
electrodes and a pair of measuring electrodes are disposed on the
surface of a specific body part as shown in FIG. 13.
[0122] For example, when the distance between the current
electrodes is short, the current density of a layer which is
relatively shallow from the surface of the specific body part is
high as compared with when the distance between the current
electrodes is long. Further, the layer which is relatively shallow
from the surface of the specific body part contains a large
quantity of subcutaneous fat, and a layer which is relatively deep
from the surface of the specific body part contains a large
quantity of visceral fat. For this reason, an impedance based on
measurement has a relatively high correlation with a body
composition indicator when a subcutaneous fat area is estimated as
the body composition indicator and has a relatively low correlation
when a visceral fat area is estimated as the specific body part.
Thus, deterioration of the accuracy of measurement of impedance in
particular becomes significant depending on what is estimated as a
body composition indicator.
[0123] Further, a body composition depends on the frequency of a
current passing through a specific body part. A description will be
given to this point by use of FIG. 14. FIG. 14 is a diagram
illustrating body tissues by an electrical equivalent circuit. As
the body tissues, skin is represented by Rs, subcutaneous fat is
represented by Rsf, a cell membrane is represented by Cm, an
intracellular fluid is represented by Ri, and an extracellular
fluid is represented by Re. Further, a muscle tissue is represented
by the cell membrane Cm, the intracellular fluid Ri and the
extracellular fluid Re. While a high-frequency current passes
through all body tissues, a low-frequency current does not pass
through the cell membrane Cm and the intracellular fluid Ri because
the cell membrane Cm acts as an insulator. Thus, the accuracy of
measurement of impedance is low due to the influence of the muscle
tissue when a current of single frequency is passed.
[0124] For example, when a high-frequency current is passed through
a specific body part, an impedance under the high influence of the
muscle tissue is measured, and the correlation when a subcutaneous
fat area is estimated as a body composition indicator is poor,
while when a low-frequency current is passed through a specific
body part, an impedance under the low influence of the muscle
tissue is measured, and the correlation when a visceral fat area or
a muscle thickness is estimated as a body composition indicator is
poor.
[0125] The present body composition meter constituted as described
above is based on the above principle and solves the problem of low
accuracy when a pair of current electrodes and a pair of measuring
electrodes are disposed.
[0126] To be more specific, according to the present body
composition meter constituted as described above, since the
multiple pairs of current electrodes are disposed on a specific
body part successively at smaller spacings and a current is
generated between each pair of current electrodes in the current
generating section, a current passes such that it depends on a
layer which is relatively shallow from the surface of the specific
body part between an inner pair of current electrodes (distance
between the current electrodes is short), a layer which is
relatively deep from the surface of the specific body part between
an outer pair of current electrodes (distance between the current
electrodes is long), and a layer which is relatively medium from
the surface of the specific body part between a pair of current
electrodes (distance between the current electrodes is medium)
disposed between the inner and outer pairs of current electrodes.
Further, since a voltage generated between the measuring electrodes
when the current generating section generates a current between
each pair of current electrodes in the voltage detecting section
and body composition indicators are estimated based on all of the
detected voltages in the body composition estimating means, body
composition indicators taking into consideration the degree of
current dependence on the layers which are relatively shallow,
relatively medium and relatively deep from the surface of the
specific body part can be estimated. Further, in particular, since
the current generating section generates a current such that the
frequency of the current gradually lowers from the outer pair of
current electrodes to the inner pair of current electrodes,
voltages can be detected according to distribution of tissues in
the specific body part, and estimation accuracy can be further
increased.
[0127] Therefore, the body composition meter of the present
invention can obtain highly accurate body composition indicators
without non-uniform body composition distribution from the surface
of a specific body part toward the center of a body when a pair of
current electrodes and a pair of measuring electrodes are disposed
on the surface of the specific body part, varying current density
distribution from the surface of the specific body part toward the
center of the body according to the distance between the current
electrodes disposed on the surface of the specific body part, and
dependency of tissues on frequency.
EXAMPLE 1
[0128] First, the specific constitution of a body composition meter
(device which estimates body composition indicators in the abdomen
by use of electrodes whose distance therebetween varies according
to the width of the abdomen of a body) according to the present
invention will be described by using primarily an external view
shown in FIG. 1 and a block diagram shown in FIG. 2.
[0129] When viewed from outside, the body composition meter as
Example 1 comprises a support 1 that comprises a group of
electrodes (first current electrodes 2a and 2b, second current
electrodes 3a and 3b, and measuring electrodes 4a and 4b), handles
5a and 5b, and an operation box 6.
[0130] The support 1 supports the electrodes, has a horseshoe shape
so that the electrodes closely contact the abdomen 30 of a body,
and also has a body part width acquiring section 7. The body part
width acquiring section 7 measures the width of the abdomen of a
body (i.e., the distance between the left and right sides of the
abdomen) by expanding or contracting its central portion. More
specifically, the support 1 comprises an adjustable arm 8 (i.e.,
two semi-horseshoe-shaped arms 8a and 8b). One end of the
semi-horseshoe-shaped arm 8a slides into the inside of one end of
the semi-horseshoe-shaped arm 8b and slides along the internal
surface thereof. Further, the sliding ends of the two
semi-horseshoe-shaped arms 8a and 8b have an encoder 9 which
comprises electrodes for detecting capacitance. The encoders 9
detect the distance when the two semi-horseshoe-shaped arms 8a and
8b are fitted around the abdomen 30 of the body. Further, one end
of the semi-horseshoe-shaped arm 8a forms a rack, one end of the
semi-horseshoe-shaped arm 8b houses a driving motor 11 whose
rotating shaft forms a pinion, and when the driving motor 11 drives
to rotate the pinion-shaped rotating shaft with the rack-shaped
portion engaging with the pinion-shaped portion, the rack-shaped
portion moves. That is, the two semi-horseshoe-shaped arms 8a and
8b slide and extend or contract automatically. Further, contact
detecting sensors 10a and 10b (such as photointerrupters and
piezoelectric sensors) which detect that the semi-horseshoe-shaped
arms 8a and 8b are in contact with the abdomen of the body are
provided on the inner sides of the other ends of the two
semi-horseshoe-shaped arms 8a and 8b.
[0131] The handles 5a and 5b are provided on the outer sides of the
bended portions of the adjustable arm 8 to help a user to hold the
support 1 easily.
[0132] The first current electrodes 2a and 2b are provided on the
inner sides of the semi-horseshoe-shaped arms 8a and 8b,
respectively, to pass a current through the abdomen 30 of the body.
The second current electrodes 3a and 3b are provided on the inner
sides of the semi-horseshoe-shaped arms 8a and 8b, respectively,
and between the first current electrodes 2a and 2b to pass a
current through the abdomen 30 of the body. The measuring
electrodes 4a and 4b are provided on the inner sides of the
semi-horseshoe-shaped arms 8a and 8b, respectively, and between the
second current electrodes 3a and 3b to detect a voltage generated
by passing a current through the abdomen 30 of the body. The
electrodes 2a, 3a and 4a and 2b, 3b and 4b are placed symmetrically
with respect to the O axis such that the distance between the
measuring electrodes 4a and 4b is 8 cm, the distance between the
second current electrodes 3a and 3b is 16 cm to 20 cm (preferably
16 cm to 18 cm), and the distance between the first current
electrodes 2a and 2b is 24 cm to 28 cm (preferably 24 cm), when the
arms 8a and 8b are in the most contracted state. In other words,
the electrodes 2a, 3a and 4a and 2b, 3b and 4b are placed
symmetrically with respect to the O axis such that the distance
between the measuring electrode 4a and the second current electrode
3a and between the measuring electrode 4b and the second current
electrode 3b is 4 cm to 6 cm (preferably 4 cm to 5 cm), and the
distance between the measuring electrode 4a and the first current
electrode 2a and between the measuring electrode 4b and the first
current electrode 2b is 8 cm to 10 cm (preferably 8 cm). The term
"distance" used herein refers to the distance from the edge of one
electrode to the edge of the other electrode.
[0133] The operation box 6 has a display section 12 and an input
section 13 on the front face of a case and incorporates a power
section 14, a time keeping section 15, a current generating section
16, a voltage detecting section 17, a storage section 18, a
computing section 19 and a control section 20.
[0134] The power section 14 supplies electric power to the sections
constituting the electrical system of the present device.
[0135] The time keeping section 15 keeps time.
[0136] The input section 13 comprises a power switch 13a and a
measurement switch 13b. The power switch 13a is used to start
supplying electric power from the power section 14. The measurement
switch 13b is used to start measurement of impedance.
[0137] The current generating section 16 switches and selects
between connections of the electrodes for passing a current (i.e.,
between connection of the first current electrodes 2a and 2b and
connection of the second current electrodes 3a and 3b) and
generates a current to be passed through the abdomen 30 of the body
under control of the control section 20. The current generating
section 16 generates a high-frequency current Aout-high (having a
frequency of 128 kHz to 512 kHz, preferably a frequency of 256 kHz)
for the first current electrodes 2a and 2b and generates a
low-frequency current Ain-low (having a frequency of 4 kHz to 12.5
kHz, preferably a frequency of 5 kHz) for the second current
electrodes 3a and 3b.
[0138] The voltage detecting section 17 detects a voltage Vout-high
generated between the measuring electrodes 4a and 4b when the
current Aout-high is passed between the first current electrodes 2a
and 2b and a voltage Vin-low generated between the measuring
electrodes 4a and 4b when the current Ain-low is passed between the
second current electrodes 3a and 3b.
[0139] The storage section 18 comprises a body composition
computing equation storage section which stores the following
various body composition computing equations (1) to (7) for
computing body composition indicators (i.e., subcutaneous fat
thickness, abdominal muscle thickness, subcutaneous fat area,
visceral fat area, total abdominal fat area, truncal fat
percentage, and whole body fat percentage) based on both an
impedance Zout-high based on the voltage Vout-high generated
between the measuring electrodes 4a and 4b when the current
Aout-high is passed between the first current electrodes 2a and 2b
and an impedance Zin-low based on the voltage Vin-low generated
between the measuring electrodes 4a and 4b when the current Ain-low
is passed between the second current electrodes 3a and 3b. The
storage section 18 also stores various other data. subcutaneous fat
thickness=11.3.times.Zin-low-0.35.times.Zout-high (1) abdominal
muscle thickness=-0.031.times.Zin-low+0.101.times.Zout-high (2)
subcutaneous fat area=23.5.times.Zin-low-19.1.times.Zout-high (3)
visceral fat area=-4.1.times.Zin-low+28.1.times.Zout-high (4) total
abdominal fat area=28.8.times.Zin-low-14.2.times.Zout-high (5)
truncal fat percentage=1.61+1.32.times.Zin-low+0.85.times.Zout-high
(6) whole body fat
percentage=0.85.times.(1.61+1.32.times.Zin-low+0.85.times.Zout-high)+-
1.1 (7)
[0140] A subcutaneous fat thickness, an abdominal muscle thickness,
a subcutaneous fat area, a visceral fat area and a total abdominal
fat area which are computed by the above body composition computing
equations (1) to (5) are highly correlated with a subcutaneous fat
thickness, an abdominal muscle thickness, a subcutaneous fat area,
a visceral fat area and a total abdominal fat area which are
determined by CT (Computed Tomography) scanning which is generally
considered to have good estimation accuracy, as shown in FIGS. 4 to
8. Further, a truncal fat percentage and a whole body fat
percentage which are computed by the above body composition
computing equations (6) and (7) are highly correlated with a
truncal fat percentage and a whole body fat percentage which are
determined by DXA (Dual X-ray Absorptiometry) which is generally
considered to have good estimation accuracy, as shown in FIGS. 9
and 10.
[0141] The computing section 19 comprises an impedance computing
section and a body composition computing section. The impedance
computing section computes the impedances Zout-high and Zin-low
based on the currents Aout-high and Ain-low generated from the
current generating section 16 and the voltages Vout-high and
Vin-low detected by the voltage detecting section 17, respectively.
The body composition computing section computes body composition
indicators (i.e., subcutaneous fat thickness, abdominal muscle
thickness, subcutaneous fat area, visceral fat area, total
abdominal fat area, truncal fat percentage, and whole body fat
percentage) by substituting the impedances Zout-high and Zin-low
computed by the impedance computing section into the body
composition computing equations (1) to (7) stored in the body
composition computing equation storage section. The computing
section 19 also computes various other data.
[0142] The display section 12 displays the body composition
indicators (i.e., subcutaneous fat thickness, abdominal muscle
thickness, subcutaneous fat area, visceral fat area, total
abdominal fat area, truncal fat percentage, and whole body fat
percentage) computed by the body composition computing section, an
estimated cross section of the abdomen of a body, and other input,
measurement and result data.
[0143] The control section 20 (i) controls supply of electric power
from the power section 14 to the sections constituting the
electrical system of the present device, based on an ON signal from
the power switch 13a, (ii) controls generation of the currents
Aout-high and Ain-low from the current generating section 16, based
on an ON signal from the measurement switch 13b, (iii) controls
computations of the impedances Zout-high and Zin-low by the
impedance computing section, based on the voltages Vout-high and
Vin-low generated between the measuring electrodes 4a and 4b from
the voltage detecting section 17, (iv) controls computations of the
body composition indicators (i.e., subcutaneous fat thickness,
abdominal muscle thickness, subcutaneous fat area, visceral fat
area, total abdominal fat area, truncal fat percentage, and whole
body fat percentage) by the body composition computing section,
based on the impedances Zout-high and Zin-low computed by the
impedance computing section and the body composition computing
equations (1) to (7) stored in the body composition computing
equation storage section, (v) controls activation of the driving
motor 11 based on an ON signal from the measurement switch 13b,
deactivation of the driving motor 11 based on an ON signal from the
contact detecting sensors 10a and 10b, and computation of the width
(body part width) between the left and right sides of the abdomen
of a specific body part by the computing section 19 based on a
detection signal from the encoders 9, (vi) controls display of
various input, measurement and result data by the display section
12, in the input, measurement and result stages, and (vii) controls
various other data.
[0144] The electrodes (the first current electrodes 2a and 2b, the
second current electrodes 3a and 3b and the measuring electrodes 4a
and 4b), the current generating section 16 and the voltage
detecting section 17 constitute a body part impedance measuring
section 21.
[0145] Next, the operations of the body composition meter (device
which estimates body composition indicators in the abdomen)
according to the present invention will be described by using
primarily a flowchart shown in FIG. 3.
[0146] First, when the power switch 13a is pressed, electric power
is supplied from the power section 14 to the sections in the
electrical system, and an initial screen as shown in FIG. 12A is
displayed on the display section 12 (STEP S1).
[0147] Then, it is determined in the control section 20 whether the
measurement switch 13b has been pressed (STEP S2). If the
measurement switch 13b has not been pressed (NO in STEP S2), this
step of measurement standby state is repeated until the measurement
switch 13b is pressed.
[0148] On the other hand, if the measurement switch 13b has been
pressed with the adjustable arm 8 fitted around the abdomen 30 of a
body such that the electrodes make close contact with the abdomen
30 (YES in STEP S2), the driving motor 11 is activated based on a
control signal from the control section 20, and the two
semi-horseshoe-shaped arms 8a and 8b thereby slide and contract
automatically. Then, when the contact detecting sensors 10a and 10b
detect that the arms 8a and 8b have made contact with the sides of
the abdomen of the body, the driving motor 11 is deactivated based
on a control signal from the control section 20, and the two
semi-horseshoe-shaped arms 8a and 8b thereby stop sliding. Then,
the stop position is detected by the electrodes which detect
capacitance in the encoders 9. In other words, the distance when
the adjustable arm 8 is fitted to the sides of the body is detected
(STEP S3).
[0149] Then, under control of the control section 20, the current
generating section 16 selects the first current electrodes 2a and
2b and generates a high-frequency current Aout-high between the
first current electrodes 2a and 2b, the voltage detecting section
17 detects a voltage Vout-high generated between the measuring
electrodes 4a and 4b at that time, the impedance computing section
computes an impedance Zout-high based on the current Aout-high
generated from the current generating section 16 and the voltage
Vout-high detected by the voltage detecting section 17, and the
computed impedance Zout-high is stored in the storage section 18
temporarily. Then, under control of the control section 20, the
current generating section 16 selects the second current electrodes
3a and 3b and generates a low-frequency current Ain-low between the
second current electrodes 3a and 3b, the voltage detecting section
17 detects a voltage Vin-low generated between the measuring
electrodes 4a and 4b at that time, the impedance computing section
computes an impedance Zin-low based on the current Ain-low
generated from the current generating section 16 and the voltage
Vin-low detected by the voltage detecting section 17, and the
impedance Zin-low is stored in the storage section 18 temporarily
(STEP S4).
[0150] Then, under control of the control section 20, the body
composition computing section computes a subcutaneous fat thickness
by substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (1) stored in the body composition
computing equation storage section and stores the computed
subcutaneous fat thickness in the storage section 18 temporarily
(STEP S5).
[0151] Then, under control of the control section 20, the body
composition computing section computes an abdominal muscle
thickness by substituting the impedances Zout-high and Zin-low
which are temporarily stored in the storage section 18 into the
body composition computing equation (2) stored in the body
composition computing equation storage section and stores the
computed abdominal muscle thickness in the storage section 18
temporarily (STEP S6).
[0152] Then, under control of the control section 20, the body
composition computing section computes a subcutaneous fat area by
substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (3) stored in the body composition
computing equation storage section and stores the computed
subcutaneous fat area in the storage section 18 temporarily (STEP
S7).
[0153] Then, under control of the control section 20, the body
composition computing section computes a visceral fat area by
substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (4) stored in the body composition
computing equation storage section and stores the computed visceral
fat area in the storage section 18 temporarily (STEP S8).
[0154] Then, under control of the control section 20, the body
composition computing section computes a total abdominal fat area
by substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (5) stored in the body composition
computing equation storage section and stores the computed total
abdominal fat area in the storage section 18 temporarily (STEP
S9).
[0155] Then, under control of the control section 20, the body
composition computing section computes a truncal fat percentage by
substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (6) stored in the body composition
computing equation storage section and stores the computed truncal
fat percentage in the storage section 18 temporarily (STEP
S10).
[0156] Then, under control of the control section 20, the body
composition computing section computes a whole body fat percentage
by substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (7) stored in the body composition
computing equation storage section and stores the computed whole
body fat percentage in the storage section 18 temporarily (STEP
S11).
[0157] Then, under control of the control section 20, the computing
section 19 compares the subcutaneous fat area and visceral fat area
stored temporarily in the storage section 18 with each other (STEP
S12). If the difference between the visceral fat area and the
subcutaneous fat area is larger than or equal to 0, the display
section 12 displays measurement results with a message "VISCERAL
FAT TYPE!" as shown in FIG. 12B. Meanwhile, if the difference
between the visceral fat area and the subcutaneous fat area is-not
larger than or equal to 0, the display section 12 displays
measurement results with a message "SUBCUTANEOUS FAT TYPE!" as
shown in FIG. 12C for a given time period and then displays a
screen for inquiring for remeasurement as shown in FIG. 12D (STEP
S13).
[0158] Then, the control section 20 determines whether the
measurement switch 13b has been pressed (STEP S14). If the
measurement switch 13b has been pressed (YES in STEP S14), the
display section 12 displays the initial screen (STEP S1) again,
thereby making it possible to carry out the above series of
measurement procedures. Meanwhile, if the measurement switch 13b
has not been pressed even if the time keeping section has kept a
certain length of time (NO in STEP S14), the power is turned off
automatically, whereby the above series of operating procedures are
ended.
[0159] According to the body composition meter of Example 1, the
support 1 changes the distance between the current electrodes 2a
and 2b, the distance between the current electrodes 3a and 3b, and
the distance between the measuring electrodes 4a and 4b according
to the width of the specific body part (i.e., the distance between
the left and right sides of the abdomen). Thus, regardless of the
width of the specific body part (i.e., the distance between the
left and right sides of the abdomen), accurate impedances in the
abdomen can be obtained, and body composition indicators can be
estimated.
EXAMPLE 2
[0160] First, the specific constitution of a body composition meter
(device which estimates body composition indicators in the abdomen
by use of electrodes whose distance therebetween does not vary
according to the width of the abdomen of a body) according to the
present invention will be described by using primarily an external
view shown in FIG. 17 and a block diagram shown in FIG. 2.
[0161] When viewed from outside, the body composition meter as
Example 2 comprises a group of electrodes (first current electrodes
2a and 2b, second current electrodes 3a and 3b, and measuring
electrodes 4a and 4b), an operation box 6, an adjustable member
202, and a support 201.
[0162] The support 201 supports the electrodes and has flexibility
and a horseshoe shape so that the electrodes can make close contact
with the abdomen 30 of a body.
[0163] The adjustable member 202 is a body part width acquiring
section 7 which expands or contracts to measure the width of the
abdomen of a body (i.e., the distance between the left and right
sides of the abdomen). In other words, the adjustable member 202
comprises a detection driving box 203, adjustable arms 204 (two
L-shaped arms 204a and 204b), and contact detecting sensors 10a and
10b, and the adjustable member 202 measures a position where the
two L-shaped arms 204a and 204b make contact with the left and
right sides of the abdomen of a body while passing through the
detection driving box 203. More specifically, the contact detecting
sensors 10a and 10b (such as photointerrupters and piezoelectric
sensors) detect that the arms 204a and 204b are in contact with the
left and right sides of the abdomen of a body and are provided on
the inner sides of the ends of the two L-shaped arms 204a and 204b.
The detection driving box 203 incorporates electrodes for detecting
capacitance (portion of an encoder 9) and a driving motor 11 whose
rotating shaft forms a pinion. Further, the two L-shaped arms 204a
and 204b each have a rack-shaped portion which passes through the
detection driving box 203, and the rack-shaped portion has
electrodes for detecting capacitance (portion of the encoder 9).
When the driving motor 11 drives to rotate the pinion-shaped
rotating shaft with the rack-shaped portion engaging with the
pinion-shaped portion in the detection driving box 203, the
rack-shaped portion moves, and a position where the contact
detecting sensors 10a and 10b have detected that the arms 204a and
204b have made contact with the left and right sides of the abdomen
of the body is detected by the portion of the encoder 9 in the
detection driving box 203 and the portion of the encoder 9 in the
portions of the two L-shaped arms 204a and 204b which pass through
the detection driving box 203.
[0164] The first current electrodes 2a and 2b are provided on both
ends of the inner side (side which contacts the abdomen 30 of the
body) of the support 201 to pass a current through the abdomen 30
of the body. The second current electrodes 3a and 3b are provided
on the inner side (side which contacts the abdomen 30 of the body)
of the support 201 and between the first current electrodes 2a and
2b to pass a current through the abdomen 30 of the body. The
measuring electrodes 4a and 4b are provided on the inner side (side
which contacts the abdomen 30 of the body) of the support 201 and
between the second current electrodes 3a and 3b to detect a voltage
generated by passing a current through the abdomen 30 of the body.
The electrodes 2a, 3a and 4a and 2b, 3b and 4b are placed
symmetrically with respect to the O axis such that the distance
between the measuring electrodes 4a and 4b is 8 cm, the distance
between the second current electrodes 3a and 3b is 16 cm to 20 cm
(preferably 16 cm to 18 cm), and the distance between the first
current electrodes 2a and 2b is 24 cm to 28 cm (preferably 24 cm).
In other words, the electrodes 2a, 3a and 4a and 2b, 3b and 4b are
placed symmetrically with respect to the O axis such that the
distance between the measuring electrode 4a and the second current
electrode 3a and between the measuring electrode 4b and the second
current electrode 3b is 4 cm to 6 cm (preferably 4 cm to 5 cm), and
the distance between the measuring electrode 4a and the first
current electrode 2a and between the measuring electrode 4b and the
first current electrode 2b is 8 cm to 10 cm (preferably 8 cm). The
term "distance" used herein refers to the distance from the edge of
one electrode to the edge of the other electrode.
[0165] The operation box 6 has a display section 12 and an input
section 13 on the front face of a case and incorporates a power
section 14, a time keeping section 15, a current generating section
16, a voltage detecting section 17, a storage section 18, a
computing section 19 and a control section 20.
[0166] The power section 14 supplies electric power to the sections
constituting the electrical system of the present device.
[0167] The time keeping section 15 keeps time.
[0168] The input section 13 comprises a power switch 13a and a
measurement switch 13b. The power switch 13a is used to start
supplying electric power from the power section 14. The measurement
switch 13b is used to start measurement of impedance.
[0169] The current generating section 16 switches and selects
between connections of the electrodes for passing a current (i.e.,
between connection of the first current electrodes 2a and 2b and
connection of the second current electrodes 3a and 3b) and
generates a current to be passed through the abdomen 30 of the body
under control of the control section 20. The current generating
section 16 generates a high-frequency current Aout-high (having a
frequency of 128 kHz to 512 kHz, preferably a frequency of 256 kHz)
for the first current electrodes 2a and 2b and generates a
low-frequency current Ain-low (having a frequency of 4 kHz to 12.5
kHz, preferably a frequency of 5 kHz) for the second current
electrodes 3a and 3b.
[0170] The voltage detecting section 17 detects a voltage Vout-high
generated between the measuring electrodes 4a and 4b when the
current Aout-high is passed between the first current electrodes 2a
and 2b and a voltage Vin-low generated between the measuring
electrodes 4a and 4b when the current Ain-low is passed between the
second current electrodes 3a and 3b.
[0171] The storage section 18 comprises a body composition
computing equation storage section which stores the following
various body composition computing equations (8) to (14) for
computing body composition indicators (i.e., subcutaneous fat
thickness, abdominal muscle thickness, subcutaneous fat area,
visceral fat area, total abdominal fat area, truncal fat
percentage, and whole body fat percentage) based on both an
impedance Zout-high based on the voltage Vout-high generated
between the measuring electrodes 4a and 4b when the current
Aout-high is passed between the first current electrodes 2a and 2b
and an impedance Zin-low based on the voltage Vin-low generated
between the measuring electrodes 4a and 4b when the current Ain-low
is passed between the second current electrodes 3a and 3b. The
storage section 18 also stores various other data. subcutaneous fat
thickness=a.times.Zin-low-b.times.Zout-high+c.times.width of
abdomen+d (8) abdominal muscle
thickness=-e.times.Zin-low+f.times.Zout-high+g+width of abdomen+h
(9) subcutaneous fat
area=i.times.Zin-low-j.times.Zout-high+k.times.width of abdomen+l
(10) visceral fat
area=-m.times.Zin-low+n.times.Zout-high+o.times.width of abdomen+p
(11) total abdominal fat
area=q.times.Zin-low-r.times.Zout-high+s.times.width of abdomen+t
(12) truncal fat
percentage=-u.times.(1/Zin-low)-v.times.(1/Zout-high)-w.times.width
of abdomen+x (13) whole body fat
percentage=0.85.times.{-u.times.(1/Zin-low).times.-v.times.(1/Zout-high).-
times.w.times.width of abdomen+x}+1.1 (14)
[0172] In the above formulae, a to x represent coefficients
(constants).
[0173] The reason that the width of the abdomen (i.e., the distance
between the left and right sides of the abdomen) is considered in
the above body composition computing equations (8) to (14) unlike
the embodiment (Example 1) in which the distances between the
electrodes vary according to the width of the abdomen of a body is
as follows. That is, since an abdominal portion with which the
electrodes desirably make contact changes according to the size of
the abdomen, an abdominal portion with which the electrodes
actually make contact differs from the abdominal portion with which
the electrodes desirably make contact in the embodiment (Example 2)
in which the distances between the electrodes do not vary according
to the width of the abdomen of a body, so that substantial errors
may be included in measured data. Hence, the width of the abdomen
is required to correct the errors. Meanwhile, in other words, in
the embodiment (Example 1) in which the distances between the
electrodes vary according to the width of the abdomen of a body,
the width of the abdomen (i.e., the distance between the left and
right sides of the abdomen) is not considered, because an abdominal
portion with which the electrodes actually make contact is the same
as an abdominal portion with which the electrodes desirably make
contact and substantial errors therefore do not occur and
correction of the errors is therefore not necessary.
[0174] The computing section 19 comprises an impedance computing
section and a body composition computing section. The impedance
computing section computes the impedances Zout-high and Zin-low
based on the currents Aout-high and Ain-low generated from the
current generating section 16 and the voltages Vout-high and
Vin-low detected by the voltage detecting section 17, respectively.
The body composition computing section computes body composition
indicators (i.e., subcutaneous fat thickness, abdominal muscle
thickness, subcutaneous fat area, visceral fat area, total
abdominal fat area, truncal fat percentage, and whole body fat
percentage) by substituting the impedances Zout-high and Zin-low
computed by the impedance computing section into the body
composition computing equations (8) to (14) stored in the body
composition computing equation storage section. The computing
section 19 also computes various other data.
[0175] The display section 12 displays the body composition
indicators (i.e., subcutaneous fat thickness, abdominal muscle
thickness, subcutaneous fat area, visceral fat area, total
abdominal fat area, truncal fat percentage, and whole body fat
percentage) computed by the body composition computing section, an
estimated cross section of the abdomen of a body, and other input,
measurement and result data.
[0176] The control section 20 (i) controls supply of electric power
from the power section 14 to the sections constituting the
electrical system of the present device, based on an ON signal from
the power switch, (ii) controls generation of the currents
Aout-high and Ain-low from the current generating section 16, based
on an ON signal from the measurement switch 13b, (iii) controls
computations of the impedances Zout-high and Zin-low by the
impedance computing section, based on the voltages Vout-high and
Vin-low generated between the measuring electrodes 4a and 4b from
the voltage detecting section 17, (iv) controls computations of the
body composition indicators (i.e., subcutaneous fat thickness,
abdominal muscle thickness, subcutaneous fat area, visceral fat
area, total abdominal fat area, truncal fat percentage, and whole
body fat percentage) by the body composition computing section,
based on the impedances Zout-high and Zin-low computed by the
impedance computing section and the body composition computing
equations (8) to (14) stored in the body composition computing
equation storage section, (v) controls activation of the driving
motor 11 based on an ON signal from the measurement switch 13b,
deactivation of the driving motor 11 based on an ON signal from the
contact detecting sensors 10a and 10b, and computation of the width
(body part width) between the left and right sides of the abdomen
of a specific body part by the computing section 19 based on a
detection signal from the encoder 9, (vi) controls display of
various input, measurement and result data by the display section
12, in the input, measurement and result stages, and (vii) controls
various other data.
[0177] The electrodes (the first current electrodes 2a and 2b, the
second current electrodes 3a and 3b and the measuring electrodes 4a
and 4b), the current generating section 16 and the voltage
detecting section 17 constitute a body part impedance measuring
section.
[0178] Next, the operations of the body composition meter (device
which estimates body composition indicators in the abdomen by use
of electrodes whose distance therebetween does not vary according
to the width of the abdomen of a body) according to the present
invention will be described by using primarily a flowchart shown in
FIG. 3.
[0179] First, when the power switch 13a is pressed, electric power
is supplied from the power section 14 to the sections in the
electrical system, and an initial screen as shown in FIG. 12A is
displayed on the display section 12 (STEP S1).
[0180] Then, it is determined in the control section 20 whether the
measurement switch 13b has been pressed (STEP S2). If the
measurement switch 13b has not been pressed (NO in STEP S2), this
step of measurement standby state is repeated until the measurement
switch 13b is pressed.
[0181] On the other hand, if the measurement switch 13b has been
pressed with the support 201 fitted around the abdomen 30 of a body
such that the electrodes make close contact with the abdomen 30
(YES in STEP S2), the driving motor 11 is activated based on a
control signal from the control section 20, and the two L-shaped
arms 204a and 204b thereby slide and contract automatically. Then,
when the contact detecting sensors 10a and 10b detect that the arms
204a and 204b have made contact with the sides of the abdomen of
the body, the driving motor 11 is deactivated based on a control
signal from the control section 20, and the two L-shaped arms 204a
and 204b thereby stop sliding. Then, the stop position is detected
by the electrodes which detect capacitance in the encoders 9. In
other words, the distance when the adjustable member 202 is fitted
to the sides of the body is detected (STEP S3).
[0182] Then, under control of the control section 20, the current
generating section 16 selects the first current electrodes 2a and
2b and generates a high-frequency current Aout-high between the
first current electrodes 2a and 2b, the voltage detecting section
17 detects a voltage Vout-high generated between the measuring
electrodes 4a and 4b at that time, the impedance computing section
computes an impedance Zout-high based on the current Aout-high
generated from the current generating section 16 and the voltage
Vout-high detected by the voltage detecting section 17, and the
computed impedance Zout-high is stored in the storage section 18
temporarily. Then, under control of the control section 20, the
current generating section 16 selects the second current electrodes
3a and 3b and generates a low-frequency current Ain-low between the
second current electrodes 3a and 3b, the voltage detecting section
17 detects a voltage Vin-low generated between the measuring
electrodes 4a and 4b at that time, the impedance computing section
computes an impedance Zin-low based on the current Ain-low
generated from the current generating section 16 and the voltage
Vin-low detected by the voltage detecting section 17, and the
computed impedance Zin-low is stored in the storage section 18
temporarily (STEP S4).
[0183] Then, under control of the control section 20, the body
composition computing section computes a subcutaneous fat thickness
by substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (8) stored in the body composition
computing equation storage section and stores the computed
subcutaneous fat thickness in the storage section 18 temporarily
(STEP S5).
[0184] Then, under control of the control section 20, the body
composition computing section computes an abdominal muscle
thickness by substituting the impedances Zout-high and Zin-low
which are temporarily stored in the storage section 18 into the
body composition computing equation (9) stored in the body
composition computing equation storage section and stores the
computed abdominal muscle thickness in the storage section 18
temporarily (STEP S6).
[0185] Then, under control of the control section 20, the body
composition computing section computes a subcutaneous fat area by
substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (10) stored in the body composition
computing equation storage section and stores the computed
subcutaneous fat area in the storage section 18 temporarily (STEP
S7).
[0186] Then, under control of the control section 20, the body
composition computing section computes a visceral fat area by
substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (11) stored in the body composition
computing equation storage section and stores the computed visceral
fat area in the storage section 18 temporarily (STEP S8).
[0187] Then, under control of the control section 20, the body
composition computing section computes a total abdominal fat area
by substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (12) stored in the body composition
computing equation storage section and stores the computed total
abdominal fat area in the storage section 18 temporarily (STEP
S9).
[0188] Then, under control of the control section 20, the body
composition computing section computes a truncal fat percentage by
substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (13) stored in the body composition
computing equation storage section and stores the computed truncal
fat percentage in the storage section 18 temporarily (STEP
S10).
[0189] Then, under control of the control section 20, the body
composition computing section computes a whole body fat percentage
by substituting the impedances Zout-high and Zin-low which are
temporarily stored in the storage section 18 into the body
composition computing equation (14) stored in the body composition
computing equation storage section and stores the computed whole
body fat percentage in the storage section 18 temporarily (STEP
S11).
[0190] Then, under control of the control section 20, the computing
section 19 compares the subcutaneous fat area and visceral fat area
stored temporarily in the storage section 18 with each other (STEP
S12). If the difference between the visceral fat area and the
subcutaneous fat area is larger than or equal to 0, the display
section 12 displays measurement results with a message "VISCERAL
FAT TYPE!" as shown in FIG. 12B. Meanwhile, if the difference
between the visceral fat area and the subcutaneous fat area is not
larger than or equal to 0, the display section 12 displays
measurement results with a message "SUBCUTANEOUS FAT TYPE!" as
shown in FIG. 12C for a given time period and then displays a
screen for inquiring for remeasurement as shown in FIG. 12D (STEP
S13).
[0191] Then, the control section 20 determines whether the
measurement switch 13b has been pressed (STEP S14). If the
measurement switch 13b has been pressed (YES in STEP S14), the
display section 12 displays the initial screen (STEP S1) again,
thereby making it possible to carry out the above series of
measurement procedures. Meanwhile, if the measurement switch 13b
has not been pressed even if the time keeping section has kept a
certain length of time (NO in STEP S14), the power is turned off
automatically, whereby the above series of operating procedures are
ended.
[0192] According to the body composition meter of Example 2, body
composition indicators are estimated in the body composition
computing section merely by performing computations by substituting
the width of a specific body part (i.e., the distance between the
left and right sides of the abdomen) acquired (measured) by the
body part width acquiring section (adjustable member 202) and
impedances computed by the impedance computing section into the
body composition computing equations stored in the body composition
computing equation storage section. Thus, body composition
indicators can be determined more accurately and more easily.
[0193] In the above Example 1, the body part width acquiring
section 7 also serves as the support 1 and acquires the width of a
body part (i.e., the distance between the left and right sides of
the abdomen) by measurement. However, the distance between the left
and right sides of the abdomen may be input through the input
section 13.
[0194] Further, in the above Example 1, the support 1 has a central
portion which expands or contracts. However, the support 1 may have
a central portion which does not expand or contract as shown in
FIG. 16, at the sacrifice of accuracy.
[0195] Further, in the above Example 1, the electrodes are disposed
on the inner side of the support 1. However, flexible elastic
members (such as springs and rubber) 64a and 64b may be provided
between a support 61 and electrodes 62a, 62b, 63a and 63b as shown
in FIG. 15 so that the electrodes provided on the support can make
closer contact with the abdomen of a body when the support is
applied to the abdomen of the body.
[0196] In the above Example 2, the width of the abdomen of a body
(i.e., the distance between the left and right sides of the
abdomen) is acquired through measurement using the adjustable
member 202. However, the distance between the left and right sides
of the abdomen may be input through the input section 13.
[0197] Further, in the above Example 2, the electrodes are disposed
on the inner side of the support 201. However, flexible elastic
members (such as springs and rubber) 264a and 264b may be provided
between a support 261 and electrodes 262a, 262b, 263a and 263b as
shown in FIG. 18 so that the electrodes provided on the support can
make closer contact with the abdomen of a body when the support is
applied to the abdomen of the body. Alternatively, flexible elastic
members (such as springs and rubber) 275a, 275b, 275a, 275b, 275a
and 275b may be provided between a support 271 and electrodes 272a,
272b, 273a, 273b, 274a and 274b as shown in FIG. 19
[0198] Further, in the above Examples 1 and 2, two pairs of current
electrodes (first current electrodes 2a and 2b and second current
electrodes 3a and 3b) are provided on the supports 1 and 201.
However, three or more pairs of current electrodes may be provided
on the supports. Further, the current electrodes may not have to be
provided on the support and may be directly placed on a specific
body part in the same arrangement as that on the support.
[0199] Further, in the above Examples 1 and 2, impedances in the
abdomen 30 of the body are measured, and body composition
indicators are estimated. However, it is also possible that
impedances in arms, legs or the like of a body are measured and
body composition indicators are estimated.
[0200] Further, in the above Examples 1 and 2, the electrodes are
disposed in the circumferential direction of the abdomen of the
body. However, the electrodes may be disposed in the longitudinal
direction (body height direction) of the abdomen of the body.
[0201] Further, in the above Examples 1 and 2, the present body
composition meter is applied to the abdomen of a human being.
However, the present device may be modified to be applicable to a
specific body part of an animal such as a dog or a cat.
* * * * *